By
CRWR – UT at
March 2005
A
tool called DSS Hydro tool for transferring around two million of historical
records from an ArcHydro geodatabase into a HEC-DSS file and back to a
geodatabase is being developed in this research for using with USACE HEC
models. This tool consists of a set of public domain utilities developed in
Visual Basic. The DSS Hydro toolbar operates in the ArcGIS ArcMap environment,
and is comprised of four commands to transfer the temporal information (Figure
1). This tool utilizes an object library and objects classes within the geodatabase
structure called DSS Time Series Catalog (DSSTSCatalog) that contains all
relevant records and descriptors to automatically transfer the time series
(Teasley et al, 2004)
The
original ArcHydro Time Series framework must be modified to create
automatically the DSSTSCatalog table inside the ArcHydro
structure when the ArcHydro schema is applied to a geodatabase. This
table contains all necessary fields that are used as the descriptors to create
the HEC-DSS files (figure 2).
Figure 2.0 Modified ArcHydro Time Series Framework
The DSSTSCatalog is populated automatically
in a geodatabase using the “Writing DSS Catalog into the geodatabase” option
included in the DSS Hydro toolbar, based on the temporal information contained
in the time series table of the geodatabase. The DSSTSCatalog is the object
class table within the geodatabase that contains the information related to the
DSS data and its pathname, and represents the key step in transforming a time
series from a geodatabase into the HEC-DSS format. The DSS pathname consists of
six parts in the following format:
/A/B/C/D/E/F/
Where
·
A -
Group name for the data such as a watershed name, study name or any identifier
which allows the records to be recognized as belonging to a group.
·
B – The
location identifier for the data. The location identifier may be a site name or
organization ID such as a USGS gage ID or the HydroID of the monitoring point.
·
C - The
parameter of the data such as flow, precipitation, storage, evaporation, etc.
·
D - the
start date of the time series, and
·
E - The
time interval for regular data or the block length for irregular interval data.
·
F - An optional
descriptor that can be used for additional information about the data.
Once the DSSTSCatalog
is created, the time series is transferred from the geodatabase to the HEC-DSS
format using the “Transferring Time Series from GDB to HEC-DSS” option of the
DSS Hydro toolbar, in order to create the HEC-DSS files that will be used for
simulation purposes. After the simulation has been completed in any HEC models,
is necessary to transfer back the time series results from the HEC-DSS files to
the geodatabase. The “Transfer HEC-DSS Time Series to GDB” option of the DSS
Hydro toolbar is used to perform this task. There are two options for
exchanging temporal information; one of them uses a filter for transferring
time series just related to one specific point, whereas another one is used to
transfer all records contained in the HEC-DSS files (Figure 3).
Figure 3.0 Time series transfer between the geodatabase and the HEC-DSS
INSTALLING THE DSS HYDRO TOOLBAR DLL
Ø Open ArcMap
Ø Go to the Customize option in the Toolbars option.
Click the “Add from file” button and select the “DSSTSBridge_Jan05.DLL” from your folder where you have the dll
Activate the “HEC-DSS TIME SERIES TOOLBAR” option…..and now you should have the DSS Toolbar in your ArcMap document
DSS Hydro Toolbar Description (After you have
installed the DLL in ArcMap)
1. Writing HEC-DSS Catalog into the geodatabase: This option allows populating automatically the DSSTSType table, which was created previously by the ArcHydro schema. This function takes the temporal information from the Time Series and the TSType tables included in the ArcHydro geodatabase. The TSType table must have the next structure in order to be able to transfer the temporal information.
2. Transferring Time Series from GDB to HEC-DSS: This function transfers all temporal information contained in the ArcHydro Time Series table into a HEC-DSS file. The DSSTSType is the key table to make this transferring.
3. Transfer HEC-DSS Time Series to the GDB without Filter. This option transfers ALL temporal information from the HEC-DSS files to the GDB.
Choose the HEC-DSS file from where you want to transfer the information. Select the number variable appearing in the A Part of the HEC-DSS file (Number 6 in this example). Select the Variable Type that should be the same appearing in the C Part of the HEC-DSS file (VOLUME-MONTHLY). Select the time interval units, and type the HEC-DSS A Part (6 for this example, and it must be the same value as appears in the A Part of the HEC-DSS table). Finally select the target geodatabase where you want to store this temporal information.
4. Transfer HEC-DSS Time Series to the GDB WITH filter. This option transfers JUST THE INFO RELATED TO ONE SPECIFIC POINT from the HEC-DSS files to the GDB.
Choose the HEC-DSS file from where you want to transfer the information. Select the HydroID of the Monitoring Point in the “Input B Part (Site ID)” box. This ID must be the same as appears in the B Part of the HEC-DSS table. Select the number variable appearing in the A Part of the HEC-DSS file (Number 6 in this example). Select the Variable Type that should be the same appearing in the C Part of the HEC-DSS file (VOLUME-MONTHLY). Select the time interval units, and type the HEC-DSS A Part (6 for this example, and it must be the same value as appears in the A Part of the HEC-DSS table). Finally select the target geodatabase where you want to store this temporal information.
Graduate Research Assistant
Center for Research in Water Resources
Department of Civil Engineering,
(512) 471-0073